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Home > Health Library > Diabetes-Related High and Low Blood Sugar Levels
When you have diabetes, you may have high blood sugar levels (hyperglycemia) or low blood sugar levels (hypoglycemia) from time to time. A cold, the flu, or other sudden illness can cause high blood sugar levels. You will learn to recognize the symptoms and distinguish between high and low blood sugar levels. Insulin and some types of diabetes medicines can cause low blood sugar levels.
Learn how to recognize and manage high and low blood sugar levels. Then you can help avoid levels that can lead to medical emergencies, such as diabetic ketoacidosis or dehydration from high blood sugar levels or loss of consciousness from severe low blood sugar levels. Most high or low blood sugar problems can be managed at home. You just need to follow your doctor's instructions.
You can help avoid blood sugar problems by following your doctor's instructions on the use of insulin or diabetes medicines, diet, and exercise. Home blood sugar testing will help you see if your blood sugar is within your target range. If you've had very low blood sugar, you may be tempted to let your sugar level run high so that you don't have another low blood sugar problem. But it's so important to keep your blood sugar in your target range. To do this, follow your treatment plan and check your blood sugar regularly.
Sometimes a woman can get diabetes during pregnancy. This is called gestational diabetes. Blood sugar levels are checked regularly during the pregnancy to keep levels within a target range.
Children who have diabetes need their parents' help to keep their blood sugar levels in a target range and to exercise safely. Be sure that children learn the symptoms of both high and low blood sugar. Then they can tell others when they need help. There are many support groups and diabetes education centers to help parents and children understand about blood sugar, exercise, diet, and medicines.
Teens especially may have a hard time keeping their blood sugar levels in control. That's because their bodies are growing and developing. Also, they want to be with their friends and eat foods that may affect their blood sugar. Having diabetes during the teen years isn't easy. But it's an excellent age to understand the disease and its treatment. Your teen can take over some of the duties of their care.
If your blood sugar level reads too high or too low but you feel fine, you may want to recheck your sugar level or recalibrate your blood glucose meter. The problem may be with either your blood sample or the machine.
High blood sugar occurs when the sugar (glucose) level in your blood rises above your target range. Your blood sugar can rise when you eat too many calories or miss taking your medicines (insulin or pills). It can also rise when you have an infection or illness, an injury, or surgery. Even emotional stress can cause your blood sugar to rise.
High blood sugar usually happens slowly over a period of hours to days. But missing a dose of insulin can cause a quick rise in blood sugar levels. Blood sugar levels just above your target range may make you feel tired and thirsty. If your blood sugar stays higher than your target range for weeks, your body will adjust to that level. You may not have as many symptoms of high blood sugar.
Unless you don't monitor your blood sugar regularly or you don't notice the symptoms of high blood sugar, you likely will have time to treat high blood sugar so that you can prevent high blood sugar emergencies. Three things can help you prevent high blood sugar problems:
Complications of high blood sugar can cause serious problems, including coma and death. Over time, high blood sugar can damage your eyes, heart, kidneys, blood vessels, and nerves.
Low blood sugar occurs when the sugar (glucose) level in your blood drops below what your body needs. Your blood sugar can drop quickly if you don't eat enough food or you skip meals. It can also happen if you take too much medicine (insulin or pills), exercise more than usual, or take certain medicines that lower blood sugar. Do not drink alcohol if you have problems noticing the early signs of low blood sugar.
People who lose weight or develop kidney problems may not need as much insulin or other medicines as they did before they lost the weight or had kidney problems. Their blood sugar may drop too low. Be sure to check your blood sugar often when your body goes through changes.
When your blood sugar level drops below 70 milligrams per deciliter (mg/dL), you will usually have symptoms of low blood sugar. This can happen quickly, in 10 to 15 minutes.
You may have symptoms of low blood sugar if your blood sugar drops from a high level to a lower level. For example, if your blood sugar level has been higher than 300 mg/dL for a week or so and the level drops suddenly to 100 mg/dL, you may have symptoms of low blood sugar. This could happen even if your blood sugar is in the target range. But if you've had diabetes for many years, you may not have symptoms of low blood sugar until your blood sugar level is very low.
If your doctor thinks you have low blood sugar levels but you aren't having symptoms, your doctor may ask you to check your blood sugar more often. You may need to check your blood sugar in the middle of the night. Or you may need to do a 3-day test using a continuous glucose monitor.
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Many things can affect how your body responds to a symptom and what kind of care you may need. These include:
You have answered all the questions. Based on your answers, you may be able to take care of this problem at home.
Symptoms of serious illness may include:
Symptoms of serious illness in a baby may include the following:
You can get dehydrated when you lose a lot of fluids because of problems like vomiting or fever.
Symptoms of dehydration can range from mild to severe. For example:
Severe dehydration means:
Moderate dehydration means:
Mild dehydration means:
Early symptoms of low blood sugar may include:
If blood sugar continues to drop, you may start to have more severe symptoms.
You can test for ketones at home using special tablets or test strips. Ketones are substances made by the body when it burns fat instead of sugar. They are a sign that your blood sugar is out of control.
To do the urine test:
Some home blood sugar meters can also measure blood ketones. You use the same finger-prick method that you use to measure blood sugar.
Symptoms of infection may include:
Symptoms of diabetic ketoacidosis may include:
Here is what you can do to treat low blood sugar. If at any point during these steps you think you are getting worse, seek care immediately.
Based on your answers, you may need care soon. The problem probably will not get better without medical care.
Based on your answers, you need emergency care.
Call 911 or other emergency services now.
Sometimes people don't want to call 911. They may think that their symptoms aren't serious or that they can just get someone else to drive them. Or they might be concerned about the cost. But based on your answers, the safest and quickest way for you to get the care you need is to call 911 for medical transport to the hospital.
Based on your answers, you may need care right away. The problem is likely to get worse without medical care.
Based on your answers, the problem may not improve without medical care.
One of the most important skills to learn is how to manage your blood sugar level. This is true whether you have type 1 diabetes, type 2 diabetes, or gestational diabetes.
Follow your doctor's instructions on the use of insulin or diabetes medicines, diet, and exercise. They will help you avoid blood sugar problems. You'll learn to recognize the symptoms and know if they're from high or low blood sugar levels. Then you can take the right steps to bring your blood sugar back to your target levels.
People who keep their blood sugar levels under control with diet, exercise, or oral diabetes medicines are less likely to have problems with high or low blood sugar levels. Do not drink alcohol if you have problems noticing the early signs of low blood sugar.
If you have symptoms of high blood sugar, check your blood sugar. Your goal is to get your level back to your target range.
Here are ways you can treat high blood sugar.
If your symptoms or blood sugar levels are getting worse or have not improved after taking these steps, seek medical care right away.
You can treat low blood sugar by eating or drinking something that has 15 grams of carbohydrate. These should be quick-sugar foods. Check your blood sugar level again 15 minutes after having a quick-sugar food to make sure your level is getting back to your target range.
Children usually need less than 15 grams of carbohydrate. Check with your doctor or diabetes educator for the amount that is right for your child.
Here are examples of quick-sugar foods that have 15 grams of carbohydrate:
If you have problems with severe low blood sugar, someone else may have to give you glucagon. This is a hormone that raises blood sugar levels quickly.
Call a doctor if any of the following occur during self-care at home:
You can help your doctor diagnose and treat your condition by being prepared for your appointment.
Current as of:
July 28, 2021
Author: Healthwise StaffMedical Review: William H. Blahd Jr. MD, FACEP - Emergency MedicineKathleen Romito MD - Family MedicineAdam Husney MD - Family Medicine
Current as of: July 28, 2021
Author: Healthwise Staff
Medical Review:William H. Blahd Jr. MD, FACEP - Emergency Medicine & Kathleen Romito MD - Family Medicine & Adam Husney MD - Family Medicine
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